Shoe for driving piles



Dec. 26,- 1939. c. G. cLl-:EsATTEL SHOE FOR DRIVING PILES Filed Sept. 27,' 1937 IVENTOR.

BY y/ w' ,4 TTORNEY.

Patented Dec. 26, 1939 UNITED STATES sHoE Foe DRIVING PILES Carlos Guillermo Cleesattel, Olivos, Argentina, assigner of one-third to Hugo C. Gollmer,

New York, N. Y.

Application September 27, 1937, Serial No. 165,882 In Argentina September 28, 1936 4 claims. (o1. rs1- 57) This invention concerns a method of and means for constructing concrete piles at site, i. e., at the location of their ultimate use; more particular it involves an improved adaptation of driving 5` tubes and guide shoes provided upon ysuch tubes for the said purposes.

It is customary in this art to ram a drive tube into the ground at the desired location the tube being provided at its lower end with a suitable l0 closure, which is called a shoe. After the tube has been rammed into the earth to 1a certain depth, a limited quantity of concrete is iilled into the tube and is compressed by a lsuitable ram vertically reciprocated in the interior of the tube. `The driving tube may at the same time be driven further down into the earth, either by blows applied to the upper end of the driving tube, or by the force transmitted to the tube from the concrete in the interior of the tube when the concrete is compressed by the stroke of the ramming device.

After the tube has been lowered tothe depth to which the concrete is eventually to extend, it is pulled out step by step, the plastic concrete being simultaneously added to the first-mentioned quantity into the tube and being cornpressed by the ramming device. As the tube is being raised, the concrete emerging from the bottom thereof spreads into the surrounding layers of earth, thus forming projections'laterally protruding from the core of the finished concrete pile `which anchor the concrete pile and render impossible a vertical displacement thereof.

Aside from other disadvantages, the procedure requires an unnecessary excess of power in the ramming operation, because the friction of the large exterior surface of the tubey and contacting with the inner wall of the hole in the earth offers a high frictional resistance to the descent of the tube. Thus comparatively heavy pile driving apparatus has to be used in order to ram down the driving tube.

Another objectionable and frequently encountered disadvantage is the sliding oli` or lateral shifting of the driving tube. One reason for this is a varying consistency of the strata of earth.

These and other disadvantages, which will be recognized hereinafter, are avoided by the instant invention, as now to be explained by way of an example. The description is to be interpreted as an illustration and not as a limitation of the invention.

The figures of the accompanying drawing show such example at progressive stages of operation; all the views are vertical detail cross-sections extending substantially through the central axis of the driving tube and the potential pile.

`The View of Fig. l is taken at the time of the beginning of the operation, e. g., just after the first measure of concrete has been introduced into the lowered driving tube.

Fig. 2 shows the driving tube at its lowermost position, i. e., when the driving proper has been completed.

Fig. 3 depicts the set-up after the first major step of withdrawal of the driving tube.

Fig. 4 is an underground detail at a still farther stage of withdrawal of the vdriving tube.

In all gures like numerals are applied to similar parts.

A novel driving tube lll of this invention may comprise a cylindrical neck portion or upper part II and a cylindrical lower part I2, part II being smaller in diameter than part I2. The head portion or lower part I2 is concentrically fastened to the upper part II by any suitable means, for instance by way of a threaded bushingk I3, which is shown to be conically flared on the outside and on the'insidaat the upper and the lower end, respectively. The upper end It of the upper part I I may be suitably attached, e. g., by thread, either directly to a retaining collarI I5 forming part of a suspension device and adapted to be suspended from cable 22 (Fig. l) or to one or more extension parts It, the last of which may be suspended by way of a. collar I5 or the like (Figs. 2 and 3). In order to avoid that a collar I5 or an extension part I6 strip the connecting thread and slide over the kpart Il or If below the driving tube Ill, an outer shoulder may be provided for end thrust upon the outside near the upper ends of said parts Il and It; thus a collar I1 may be affixed, e. g., welded underneath the upper end It onto the parts II and lli, on their exterior circumferences.

The lengthof the lower part l2 is preferably several times larger than the diameter thereof, in order to insure proper guidance in the earth of the whole descending driving tube i0.

A novel guide shoe I8 may cooperate with the novel drive tube It. This guide shoe I8 cornprises a raised center portion shown in the drawing as a hollow cone. This shoe may be provided with a rim I9 with an outside diameter slightly larger than that of the lower part I2 of the drive tube I0. This shoe serves as a closure for the tube, the rim seating as a ange onto the open bottom end of the lower part I2 of the driving tube I l), so that it represents a tool with a Shoal end. The apex of the cone-shaped shoe I8 may point up into tube III, as shown.

It is easily seen that there is no friction between the neck portion or the upper contracted part II (or extension I 6) of the driving tube I0 and the wall 3D of the hole formed by the descending shoe I8. There is friction only between the lower part I2 and the wall 3l! of the hole. Thus the losses caused by friction during the operating of this device are small in comparison with driving tubes of the prior art.

Experience has further shown that the special shape of the guide shoe I8 insures that the whole Sliding tube Ii) moves vertically downward without any lateral displacement.

It is easily seen, and has been proved by experience, that the cone of the guiding shoe I8 is instrumental in forcing the concrete radially out of the lower part I2 of the driving tube II), so that the concrete spreads like a mushroom. The shoe acts as a spreader, greatly facilitating and accentuating the formation of the projection 2l at the foot of the finished pile as will be more fully described hereinafter.

The method of using the driving tube I of this invention is progressively illustrated in Figs. 1 to 4. The earth is rst excavated to a certain depth below the surface Zll, and the driving tube Ill, and the guide shoe I8 are positioned in the excavation (Fig. 1). But before this is done the hollow part of shoe I8 is filled with sand 2l or other suitable anti-friction material. During this part of the work, the driving tube I0 may be held in an upright position by theropes or cable 22 operated by and depending from any suitable means, for instance a winch and a boom, respectively (not shown). The interior of the driving tube I0 is then filled up to a low level (Fig. l) with a suitable quantity of concrete 23.

Now the ram 2li, which is arranged for reciprocation by way of a rope 25, is put to work in the manner well known in the art, ramming the concrete 23 in the driving tube IIB. The pressure is transmitted to the guide shoe I8 and drives guide shoe I8 down into the earth. Due to its weight the driving tube III moves down, following the descending guide shoe I8, the holding ropes 22 being paid out in accordance with the progress of the downward movement of the driving tube Ill. The operation is continued until the guiding shoe I8 has reached the desired depth (Fig. 2), the driving tube I Il, and more particularly the neck portion thereof, being elongated at intervals during the operation, if necessary, by insertion of one or more extensions I6.

After the desired depth has been reached, the driving tube I0 is withdrawn by means of cable or ropes 22 to an intermediate level 26 (Fig. 3), and the ram 24 preferably continues to operate during this phase of the work. The concrete 23 which had been stored in the lower part I2 of the driving tube I0 is forced out of the tube into the soft layers of the earth. The conical apex of the guide shoe I8 radially disperses and squashes the extruded material, and a lowermost and biggestconcrete head 27 is formed at the foot of the pile, so that, after the concrete has hardened, the pile is firmly founded'and rooted in the ground.

But in the meantime another charge I9 of concrete has been filled and rammed into the driving tube IG; the tube is again Withdrawn; and ram 24 and lifting ropes 22 are simultaneously operated. As before, the concrete is impacted, and forced to spread radially into the soft layers of the earth, forming another peripheral projection 3l at a higher level of the pile (Fig. 4).

The procedure is repeated until the whole pile has been formed, and will be noted that the restricted neck II, I6 also facilitates the withdrawal of tube I0.

As customary, reinforcing cages comprising for instance iron rods 28 and cross members 32 may be inserted into the driving tube Illduring the formation of the pile.

Having thus described my invention in detail, yet I do not wish to be limited thereby, except as the state of the art and the appended claims may require, for it is obvious that various modifications and changes may be made in the form of embodiment of my invention, without departing from the spirit and scope thereof.

What I claim is:

l. A shoe fitting adapted to close the lower end of a driving tube when said shoe is fitted onto said tube and having a central raised portion on said shoe adapted to extend into said tube and serving to spread apart concrete extruded from said tube onto said shoe.

2. A shoe for closing the lower end of a driving tube for constructing concrete piles, comprising a flat rim portion serving as a flange and a conical central portion arising from said rim portion with a root diameter fitting the tube and serving to spread concrete extruded onto said shoe from said tube.

3. As a shoe for a driving tube for concrete piles, a hollow cone, `the apex at said cone serving to spread material extruded from the tube, and the hollow bottom of said cone serving to receive granules facilitating the driving.

4. Constructing a concrete pile, comprising driving a conical hollow shoe ahead of a driving tube, but with the apex of the shoe extending into the tube, into the ground and ramming concrete onto the apex of said shoe so that the concrete is subterraneously spread and squashed by said shoe when the ramming is continued lafter the tube has at least partly been withdrawn.

CARLOS GUILLERMO CLEESAT'IEL. 

